PORUBSKÝ, Štefan. Sperner type theorems for generalized divisors. Annales Mathematicae Silesianae, [S. l.], v. 16, p. 27–42, 2003. Disponível em: https://journals.us.edu.pl/index.php/AMSIL/article/view/14106. Acesso em: 18 dec. 2025.